Conventionally, an electric power steering control device that controls the electric motor of the electric power steering device is known. For example, according to a disclosure in a patent document, Japanese Patent No. 5575205 (patent document 1), an amount of heat generation is estimated from the amount of electric current, for performing an overheat protection.
In the patent document 1, one driver is provided for one group of three-phase circuit coils. In the patent document 1, no overheat protection is discussed for the plural sets of the driver, and the group of coils in the control device.